fix: rollback with no id (#2231)

Fixes #2103

Author: surbhigarg92

observability-test/transaction.ts

@@ -501,14 +501,14 @@ describe('Transaction', () => {
       transaction.id = ID;
     });
 
-    it('error with unset `id`', done => {
+    it('no error with unset `id`', done => {
       const expectedError = new Error(
         'Transaction ID is unknown, nothing to rollback.'
       );
       delete transaction.id;
 
       transaction.rollback(err => {
-        assert.deepStrictEqual(err, expectedError);
+        assert.deepStrictEqual(err, null);
 
         const exportResults = extractExportedSpans();
         const actualSpanNames = exportResults.spanNames;
@@ -521,7 +521,9 @@ describe('Transaction', () => {
           `span names mismatch:\n\tGot:  ${actualSpanNames}\n\tWant: ${expectedSpanNames}`
         );
 
-        const expectedEventNames = [];
+        const expectedEventNames = [
+          'Transaction ID is unknown, nothing to rollback.',
+        ];
         assert.deepStrictEqual(
           actualEventNames,
           expectedEventNames,
@@ -532,12 +534,12 @@ describe('Transaction', () => {
         const spans = exportResults.spans;
         const firstSpan = spans[0];
         assert.strictEqual(
-          SpanStatusCode.ERROR,
+          SpanStatusCode.UNSET,
           firstSpan.status.code,
-          'Unexpected an span status code'
+          'Unexpected span status code'
         );
         assert.strictEqual(
-          expectedError.message,
+          undefined,
           firstSpan.status.message,
           'Unexpected span status message'
         );

src/transaction.ts

@@ -2517,12 +2517,9 @@ export class Transaction extends Dml {
     };
     return startTrace('Transaction.rollback', traceConfig, span => {
       if (!this.id) {
-        const err = new Error(
-          'Transaction ID is unknown, nothing to rollback.'
-        ) as ServiceError;
-        setSpanError(span, err);
+        span.addEvent('Transaction ID is unknown, nothing to rollback.');
         span.end();
-        callback!(err);
+        callback(null);
         return;
       }
 

test/transaction.ts

@@ -1975,15 +1975,10 @@ describe('Transaction', () => {
         transaction.id = ID;
       });
 
-      it('should return an error if the `id` is not set', done => {
-        const expectedError = new Error(
-          'Transaction ID is unknown, nothing to rollback.'
-        );
-
+      it('should not return an error if the `id` is not set', done => {
         delete transaction.id;
-
         transaction.rollback(err => {
-          assert.deepStrictEqual(err, expectedError);
+          assert.deepStrictEqual(err, null);
           done();
         });
       });